How Far Apart Should Decking Boards Be?

M. John

How far apart should decking boards be? When building your deck, the boards should not be too far apart and neither should they be too close. The gap between your ultra decking allows the board to expand and contract without shifting from its original position.

Why Your Decking Board Needs Spacing

Factoring space into your considerations when planning your decking project is importantcomplete short image of a composite prpject. We have gathered a few reasons to consider this, among which is the fact that spacing helps to prevent composite boards from warping or cracking. Now that this is so, how far apart then should your decking board be?

Allows Expansion and Contraction

Both composite decking and wood need spacing to make it expand and contract without damage. When installing your decking, you should place the decking far apart to keep the wood from cracking. It will also keep the board in place.

When there are temperature changes, wood can absorb moisture and can expand. It can also repel moisture, thereby making the wood contract. Although it does not absorb moisture, the same goes with composite but will expand when the temperature is hot. It will also contract when the weather is cold.

Makes Cleaning Easier

When you place the decking board apart, it will make cleaning the deck easier. Water will be able to drain away from the deck when you wash it. It will also make removing dirt and debris easier.

Allows Water Drainage

Water can accumulate on your deck when it rains. When your wood deck absorbs water, it can make it rot in time. But, if you place the decking board apart, water will be able to drain away from the deck easily.

Improve Air Circulation

The space between the decking boards will improve the aeration. It will allow the wood to dry, thereby preventing it from absorbing moisture.

Factors That Influence Decking Spacing

Wood Specie

The type of plank you choose for your decking can determine how far apart you place your deckings. When choosing the kind of wood for the deck, consider the properties of the wood. Apart from that, you have it in mind that wood absorbs moisture when humidity is high.

Woods, like pressure-treated pines, contain moisture and will shrink when humidity is low. Hardwood, cedar, and redwood also absorb moisture with different expanding and contracting properties. For the best results, you can consider working with a professional who knows the gap size for each wood type.

Moisture Level 

Wood with high moisture content will expand more than dry wood. It would help if you considered this when placing the deckings apart. With this in mind, while installing your decking board, the space between the deckings should not be too far apart.


Composite boards expand when the weather is hot. If you stay in a hot region, how far apart you place your decking board is vital. The space between the composite decking will give room for expansion. The deckings will be able to expand freely without coming in contact with each other. It, in turn, will keep the board in its fixed position. Besides that, it will stop decking from warping. So, how far apart should your decking board be?

How Far Apart Should Your Decking Boards Be?

The acceptable spacing between the deckings should be between ⅛ inch and ¼ inch. So, how far apart your decking board should be is between ⅛ inch and ¼ inch. For the composite decking, the size gap between the composite boards should be ⅛ inch.

When Installing wood decking, consider how dry the wood is before deciding whether to use a size gap of ¼ inch or ⅛ inch. For pressure-treated wood, you should leave no gap between the decking. A reason for this is that when the decking dries, the wood will shrink, leaving a gap between the deckings.


How far apart your decking board should be is between ¼ and ⅛ inch. For the composite decking, place the board ⅛ inch apart. It would be best to consider the moisture level of the wood before deciding on ¼ or ⅛ inch.


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